In patients with short bowel syndrome and excessive ostomy losses, salt depletion is associated with failure to thrive. An easy way to screen for this is checking a “spot” urine sodium level; a urine sodium <10 mmol/L is too low. While this has been recognized in infants for a long time, a recent case report shows that this can be an issue for older children (up to 19 years) as well (Nutr Clin Pract 2014 vol. 29 no. 397-401 -thanks to Kipp Ellsworth’s twitter feed for this reference & link: http://goo.gl/TkjKyd).
The authors conclusion: “We advise that patients of all ages with high stoma output have routine urine sodium levels checked, particularly in the setting of weight loss or poor gain. Furthermore, instances of TBSD [total body salt depletion] should be treated with sodium supplementation.”